Magnet-locking device



0. THOMPSON.

MAGNET LOCKING DEVICE, APPLICATION F |LED NOV. 10.1917- RENEWED DEC. [5. $921.

5 swans-sneer I. 7

Si -L INVENTOR 0/ 2 7/10/7930 BY Wm ATTORNEY Patented Jan. 31, 1922.

0. THOMPSON.

MAGNET LOCKING DEVICE.

' APPLIQATION FILED NOV. 10, 1917. RENEWED 02c. 15, 1921. 1,404,910, Patented Jan. 31, 1922.

5 SHEETS-SHEET 2.

EQ-l

INVENTOR 0/02 7770/4060 ATTORNEY,

0. THOMPSON.

v MAGNET LOCKING-DEVICE. APPLICATION FHJED NOV. 10,1917. RENEWED nzc. 15,1921.

1,404,910, Patented Jan. 31, 1922.

5 suns-sum a.

INVENTOR 0/02 Thom 0.50

ATTORNEY 0. THOMPSON. MAGNET LOCKING DEVICE.

APPLlCATlON FILED NOV. 10, I917- RENEWED DEC- 15,1921- 5 SHEETSSHEET 4- Patented Jan. 31, 1922.

I IV I/ E N TOR 0/0/ WW ,4 TTOR/VE Y Q. THOMPSON. MAGNET LOCKING DEVICE- APPLICATION lFlLED NOV. 10, 1917. nsuzwsu use. 15.1921.

Patented Jan. 31, 1922.

5 SHEETS-SHEET 5- d/a/ Mam m; BY,

A TTORNEY UNITED ,sT s IPFATENT onor THOMPSON, on NEW YORK, N. Y.

I bling of the various vviate the necessity turbing noises.

OFFICE.

MAGNET-LOCKING DEVICE.

Application filed November 10, 1917, Serial No. 201,358.

To all whom 2'27 may concern:

Be it known that I, OLorT oMrsoN, a citizen of Sweden, and a resident of the borough and county of Bronx, in the city and State of N ew York, have invented certain new and useful Improvements in Magnet- Locking Devices, of whichthe following is a specification.

This invention consists ofa locking device for electro-magnets, and includes mechanical means for temporarily retainin the core or cores of the latter, or a part carrying the same, in its or their inward position.

One object of the invention is to produce a device of the nature set forth which shall. operate to keep the movable part ofa solenoid mechanically locked when drawn into closed position, so long as an electric current remains thereon, but will automaticallyrelease the said part and permit it to recede to an open position whenever the flow of current .is interrupted.

Another object is the production of a device of the class mentioned capable of maintaining the operative part of a solenoid mechanically locked in the manner aforesaid, with but a fractional amount of the current expended to draw the .aid part to its closed position.

A further object is, to provide a device of the character described which shall admit of adjustment so as to hold the working part of anelectro-magnet,temporarily locked at any suitable distancefrom the closing point thereof, and subsequently to effect its release at a predetermined.period.

A still further object is the provision of a device of the type specified which shall obof accurate workmanship either in the manufacture or in the assemparts thereof, and yet will insure'eflicient and noiseless operation.

Still another object is to-supply a device of the species referred to, which shall be composed of few, simple and strong parts, easily kept in working order and repair.

Other objects and advantages will become apparent as the specification.proceeds.

Electromagnets heretofore employed for opening or settingswitches, and the like, have most always been subjected to hammering between the meeting ends of their cores, which obviously wrought injury to these parts, besides creating objectionable and dis- The defect here mentioned is especially noticeable with magnets that Specification of Letters Patent.

Patented Jan. 31, 1922. Renewed December 15, 1921.

are energized by alternating electric currents, and is caused by the force acting against one or both of the cores, momentarily mastering the pull of the magnet, which latter almost instantly recovers and overcomes the outward pull, thus bringing the core ends again quickly together. This action of the cores, rapidly breakingaway and returning to contact with each other, is disagreeably intensified when theirv opposed ends are not in absolute parallelism. For this reason, the meeting faces of the cores have had vto be carefully scraped off to a'bearing fit, one against the other, which is a tedious and expensive operation, as only a competent mechanic of the highest class is capable of accomplishing this work, with studious application. ,Even then, the re peated impact due to occurring wear and lost motion between the cores causes them to lose their endwise alignment" eventually Furthermore, a great deal of current is wasted, on account of it having to remain onthe magnet coil with full force while the cores are in their inwardposition, and be sides a considerable heatingup of the coil takes place, which also has an ill effect. The several disadvantages resulting from the employment of the old form of electro-mag nets, above discussed, are done away with'by the present invention.

Generally described, the invention comprises a pair of electro-magnets of different power; The stronger one of these magnets acts upon a core, or opposed cores, only one of which need be movable. An element 'ca pablc of shifting the load to be moved carries the core acted upon mainly by the stronger magnet, the inward movement of this element brings it underthe control of a lock-mechanism operated. with a reduced current'flowingfirst through the weaker magnet. hen the How of current is interrupted, the lock releasesthe load pulling element and the cores become separated.

The final outwardmovement of the element ing less than the whole.

It will be obvious to persons skilled in the Serial No. 522,722.

' art. to which the invention appertains upon becoming'conversant with the details thereof, that the same may be incorporated in 7 Therefore, the

Figure I gives a side view of one form of the invention, the working parts thereof being shown in'closed' position;

I Fig. II isa like view, with. workingparts j in open positiony s a view similar to. Fig. I, rep- Fig. III

resenting a modified form of the invention,

with the working parts closed;

Fig. IV is acorresponding view of the latter named form, showing the working parts open as-in Fig. II;

Fig.1 V is a front elevation or left-hand end view of the said modified form v )FigziVI is a diagrammatic view of the lectriowiring mployed in the construction illustrated in F gS- L and v5 7 fFigxYVII is aside viewpf a further modification, with'the working parts in a closedv position;

" modified forinof tlie-i1ivention,'witli the op- Fig. ,VIII shows the same modified st r-Li c ture as the preceding view butfwiththe working parts in pen posit on;

Fig. IX- is a front or end elevationoftlie as seen from the left hand side;

'iodified form shown'in Figs. VII and VIII,

. Fig. X is a'dlagram ofthe electric wiring used in the modification last mentioned.

shown n closed 13081131011};

' Fig. X II is asirnilar view 'ofthe. same erative parts-in openposition; and r V Fig. XIIIfis a front elevation'of the last {named modified form as seen fromthe left hand side of Fig. XII; a "portion-eta cer- V tain-element being broken awa :Descr'ibing first that form of .;the inven tion whiclr-isillustrated in FigsIhnd II,

the V numeral lri denotes a frame appertaming toan electro-magnet of'known construction; This frame usually consists 'o f a casting comprising parallel sides; one of I. whichronly-i's shown, the same constituting.

the near sideof the frame as seen in the two views referred to, and being .joinedto the Y opposite side by an elbow shaped or angu- Iar connecting "piece 2', indicated by dotted .j lines The said frame further includes su'-- perposecL-integrally formed arms3, 4c; 5

shoulders 6;? and anab'utmentS. Som'eof; these elements are provided in duplicate,"

. that is; 'on' both sides of the frame alike.

Screw-threaded bosses I9 and 10 are formed" in the back of the frame, near the top and bottom thereof respectivelyffor the recepcatch engaged itogetherfand so non ofbolts wherewiththeframe canbeiat tachedto aprimary support.

-"Pivot'pins 11 and 1 2 are supported turns I I ,versely of. the frame by the arms I and 5,

respectively." Between the arms 3 and dis tened by screws to the outer ends of the lat- I ter named arms, in front. .TheeoilL1-5 is designed to operate'upon a pair 'ofnnagnet cores consist ng of two approximately equal' parts 20, 21 which respectively enter it through itsopposite ends. The partsQOand i 21"are secured at their outer extremities to levers 22 and 23,journalled'on'the-before mentioned pivot-pins 11 and 12.

Forwardly oftheir pivots; the levers '22- and 23 are provided with fingers 24c and 25, l.

extending oppositely. therefrom so as to. :be

' directedone toward theother. Preferably,- V

the finger 24 is bentdownwardly at the f outer end toform a hook-shaped latch 26,f

side 'of the finger25; frs shown Fig. I I,

been parted by their respective lever-s22 and- 23' swinging by gravity both out ward away 7 1;

from each other, owing; to the electric cur rent 'beingcut out ofthemagneti 15; But

when the lattenis energized; to .drawjthe two cores together 'into the position repre-j sentedinFigiI,then"the levers 22 and23 are swung'both inward so thatjthe latch .Fig. XIlis afside elevation of-an addi tionalmodification a certain portion thereof bein i broken away, andthe operative parts 7 and catch i become engaged;

1 On. the inner edge oftheflever 23, just, above its pivot 12; is- .provi'de'cha stop 29j, V

which'comes into contact with-the abutment 8, and prevents .this lever fromstriking the ZllOO i magnetcoil 15 withtoomuch force,- when the 'coreQl is pulledintoits innermost p'osit1on therein' lhaouterinoStZlim-it of-t'ravel of the said lever 23 isregulated. by n'eans of an adjustable stop consisting ofa screw.

30, threaded as 'at'28 into'thelower end o f the lever, inwardly of the pivot 12 and a stop 31,- formed on the underside thereof,

rearwardly of the -pivot"f11, and arranged to bear upon the topedgeofthesaid corr.' necting piece. The lever 23 is further pro{ 'vided, (in its outer edge -with ears 12.0; I

which onlyiis"shownftheisame affording I by tlie. electro-ma'gnet. i

means 'ofattachment-for some objectadapt I e'd'for actuation-b the-lever, moved through i f- V the agency of the opposed cores controlled f y j i25 The'distancefrom'the "centre of the-pivot:

11 to the offset of the latch 26 determines thefextent of'pu'llto ibeexertedby thef mag: 2. l

long as:

V 0' mounted a magnetic wire coil 10, which s held against the shoulders 6 and? in the 7 rear, by means of clamps 16 and 17 fasters to i which the two latter are in this position, no electric current need be expended'upon the core 21 to resist a load actingto pull out the thereto connected end of the lever 23. However, the current mustlremain on the coil 15, for/otherwise, the weight of the levers 22and 23 would cause them to separate and drop into their lowermost positions, as indicated in Fig. II. The advantage of using the latch and catch, though'the current remains on the magnet and cores, is that they constitute a] lock preventing interrelative movement between the operative parts. The closer the latch and catch approach the centreof the pivot 11, the less is the force required to keep them interlocked. WVhen the said levers move inwardly towards each other, the lever 23* generally is the first to reach its limit of movement, due to the stop 29 thereon striking against the'abutment 8 onthe frame, and then the lever 22 completes its inward swinging stroke, whereupon the latch 26 takes over the catch 27 so as to be engaged thereby. As shown in Fig. II, the-latch 26 does not leave the extended end of the finger 25 beyond the catch 27 whenever it is disengaged. I i

i The electrical energy'required to be spent in order to maintain the said parts in engagement is considerably less than what is needed for the cores 20 and 21.-- Consequently,a very much weaker magnet could be used for the purpose, with a correspondingly diminished expenditure of electric current, as in the forms of the invention hereinafter described.-

I A construction embodying this principle is disclosed in Figs. III toVI, inclusive. In these several views, all parts substantially the equivalent of those already] described are designated by the same reference characters, while such elements as involve material changes in form, location, or function are denoted'by corresponding characletter-exponents have been suflixeda y Referring to the figures just named, the construction therein shown comprises a frame having parallel sides -1 and 1, connec-tedbya transverse'member 2. Pro jecting from the said frame, forwardly thereof, are arms 3,4: and 5, preferably made integraltherewith. Shoulders 6 and 7 are further formed on the frame. At the outer end of the arm 5 is an abutment'S,

Bosses 9 and 10 are providedat the'rear of the frame,the samebeing'threaded to receive bolts which fasten the latter to a primarysupport. Pivot-pins 1'1 and 12 are also fitted in the arms 4 and 5, transversely of the frame.

' In-the modification exemplifiedby Figs. III to VI, the electro-m'agnet is composed of two wire coils land 15 onemade with few'turns of heavy wire, and the other having'many turns of fine wire. As seen in Figs. III and IV, these coils are placed tandem, and held against the shoulders 6 and 7 by clamps l6 and 17.

.Oppositely located. cores 20 and 21 are made to enter the said coils 15 and 15, from the outer ends thereof, respectively. Fig. V indicates how each of these cores may be built up of laminated strips of metal, as 21 21 and2l, insulated from one an other longitudinally. The cores are respectively secured,at. their outer extremities, to levers 22 and 23, pivoted on the aforesaid pins 11 and 12.

A stop 29 is provided on the outer edge of the lever 23, near its lower end, in position to contact with a screw 30, adjustably set in thebefore mentioned abutment 8; A similar stop 31 projects from the underside of the lever 22, and limits the latters drop when abutting'against the top edge of the transverse member 2 ofthe frame.

.Ears32 are further provided on the outer edge of the lever 23, intermediately thereof,' to furnish attaching means for an object to be. actuated, as in theform of the invention first above described. It is understood that this'object represents a force opposing-the inward movement of the lever 23, which overcomes the pulling strain upon it, through the action of the said magnet coils and cores.

At the lower, forward end of the lever 22 is provided a pair of fingers 33, depending therefrom directly under the levers fulcrum 11. These fingers act as-a stop for the lever, limiting the upward swinging movement thereof by 'contact'with the face of the transverse frame member 2*.

In the hub of the said 193 81 22 is formed a ledge 34, between the'fingei s 33 above mentioned; Uponthis ledge rests the upper end of a latch 35, made preferably of a:

hardenedsteel plate. This latch is guided at its lowerend and also near the middle on the shanks of screws 36 and 37, that are entered into suitable openings in the saidtransverse member 2. Around' the screw- 36 is placed a helical compression spring 38, which bears with one end against the'lower extremity of the latch 35, and is received at the other end in a recess 39, providedtherefor in the member 2". A larger orslightly elongated aperture 40 is made in this latch, at a substantially central point between the two screws 36, 37, through which aperture a rod 41 is passed. The forward end of the'latter is adjustably received in a fork 4C2, hingedly connected by a pin 43, to an car 4 1, projecting inwardly from the lever 23. v When the electric current is turned off the magnetic coils-15'-" and 15 and the lever 22 has dropped backupon the transverse memr ber21 asindicated 'inFig; IV the ledge 34:

34. inthat case is swung-in a way to cause thelatch 35to tilt in a; rearward direction,

so thatthe top and bottom edges of the aper:

ture 40 exert a. binding actionfupon the rod 4:1,.Wll10l11S accentuated by the spring. 38

tending toforcethe lower end o'i the latch 35 intheopposite" direction Thus the rod 41 and the lever 23 pivotally connectedtherer with are held and prevented from belng pulled away by a load which the-coils 15 and 15% would normally :resist. v J

From one face, preferably ,the innerone of the transverse frame member 2, extends a an ear 45and to the latter-is 'fulcrumeda' lever 46, arranged'to oscillate ion the shank of a screw 47, entered'into the said ear. .1AIL- other screw 48 is also passed through theear 45, above the screw/l7. To the-upper screw 48- is; attached; one terminalfof altension 7 spring 49, the other end whereof is anchored as at 50, to the lever 46. r Thefree end oftherod 41, which passes throughthe member 2 extends asuiiicient distance rearwardl to be brought up against this lever and pus ba-clr lthe'same, so that the centrefline of pull-of the spring will pass the central alignment 7 T of the ear-45, screw 47 andpoint of conne'c I to complete the outwardswing of-the lever,

' f lever, strikes against therearwardly project tion50,; 'When' this occurs, the spring49acts 46,; until; a nose or protuberance 51, located on the remote sideofthefulcrum ofthe said ingend'of the screw 185 The outward swing of theleveredis'thereby limited, as shown in Fig. III; This movement of the'lever is utilized to break a circuit passing through a shoe '52 and;a pair of contact pieces 53, 54:,

carried in; the" lower portion of; the frame 7 .i g ,1 n ember2f and properly insulated therefrom;

The: shoe 52 is-held with"interposed insula}- tion, from the lower end of the lever 46,;An

. V numeral 61,- is' connected to;=,the

" Q'Wlien the lever 46 stands in? the position electricrwire 57 leads from the contact153 to the junction'between the windings-oi the "coils 1 5 and 15 asindicated at'58, FigsVI; -'Ihe numeral-59' denotes one of the linejwires a) which the contact 54:, andthe; end wire of the; coil '15 are connected the latter :as at 60. The other line'wireydesignated by the end wire of shown in Fig. III, andalsolind'icated by full .7 lar e- Warm,

neoaaio 15'" which at'tha t time is:inzseriestherewith; The coil 15 aspreviously stated has many turns'of finewire and-therefore lets through or consumes but 'a very smallamount of:,cur-' rent. Hence this coil l5 'will only require a fractional part ofthe' power expendedto on'the rod 41, and prevents the partingof the a V a core 21'," withits lever. 23, froinfthe'core. 20.;

But, assoon as one of? the linewires59z and 61 is cutout, the overbalanced levers 22v and 23. swing outwardly, and theiledge3a as be fore explained, moves away from the upper edge of the latch 35, which; isthereby en-1;

abled to align itself perpendicularly,upon

the shanks of thescrews 36 fand'3q", so that the top and bottom edges of the; aperture 40 loosen their grip'oir the [rod 41; his the a latter moves outwardly at-that time, it is H i arranged to reset the lever I6 in its previous position by meansofa-screw 63:, adjustably held inthe end of the rod, in'axial alignment therewith. Thisscrewiis positionedsoas to strikewith the underside ofjits ,headfagainst';

the back or the leverfdwhich then advances? to the position represented iii-Fig; IV where- 7 upon tllj Sl1OB 52 "closes? the gap intervening 7 between :it andithecontacts 53,: 5.4:,thejcoil '15" is short circuited, ire, placed inshunt-re lation to the line.58',j 57 and 5 9,: and the 1 elecq' trio current flows along l-amore commodious s and directlpath thi'oughf-the said coil 1751' {f I Whenfthis coil becomes energized, itexerts a its torque primarily; upon; the coref21, and a subsequently 'on'the; core -20, whereby the cycle vof operation is repeated, the-latch 35. j again; lockingwith; therod'el: mechanically;

' fIhe outward swing drop of-the lever 23, isi V predetermined by ;the;adjusltment of-the t 1170: :7 fled construction, the core 20 is arrangedtoi screw 30? againstthe stop 29: fIInthismodimove; into inward position first,' and, is imr' niediately-r-met by1-thecore;2 1. TlIQ PIBClSG- 7 time at a which thefend iofthe rod 4:1 is to hit v the front edge of; the lever: 46 or the 'head of the screwi63will 1511111101 press :back against 'th'e rear.edgeiofthesamelever, can beflaccuji rately regulated to caused-he said; coresq-todistance, the nijechaiiical locking ofthe parts app h shi-other; within; a y required 1.20 7 taking place directly after "the electric cur l Y5 rent has been --dev'iat ed .to enter the weaker magnet first,fivhenifthe magnet coils' jare a series; "At this. moment, a slightlf outwardfc veme s-0 f efde izOc urs;whichfisiinri dicated zit-6 L Fig. III, and ,serves gfurtherr'toi V V V increase the bindingfi'action of:thej'rotlfl r, lines in Fig;V I,:;the electric current-must passlthrougl the coil 15 from its outer end f f60, and thence fiow' through the heavier coil lit I .frame comprises parallel sides 1 and 1,

joined by a connecting piece 2 and provided with arms 3, 4 and 5 preferably integral therewith. Bosses 9 are formed on the sides of this frame, with suitable apertures for bolts to hold it to a primary support. Pivot pins 11 and 12 are fitted across the arms 4 and 5 respectively.

A major or relatively strong electro-magnet 15 with few turns of heavywire, is

placed in the upper part of the frame, and a minor or relatively weak electro-magnet, with many turns of fine wire is located in the lowerpart of the same. The latter-named magnet may consist of a single wire coil 15, as shown, in Fig. VIII, or of three coils 15, 15, and 15 such as appertain to a three phase-electro-magnet, and areillustrated in Fig. VII. V

The magnet 15 is held by a clamp 17, fastening it against the arm 3. This major magnet is designed to act upon opposed cores 2O" and 21. The core 20 is' rigidly attached to the arm 3 and therefore immovable, while the core 21 is carried bv-a lever 2-3, fulcrumed on the pivot pin 12.

A bell crank lever is pivoted on the pin 11, with its short arm 24 turned towards a finger- 25' projecting from the inner edge of the lever 23. The arm 24* is formed with an overhung latch 26, adapted to engage a catch .27 011 the finger 25, when the core 21, is energized to pull the lever 23 into the pos 1' tion represented in Fig. VII.

The lever 23 is provided on its outer edg with apair of ears'32, which in the present modification are located directly opposite the finger 25 formed on the inner edge of the lever. As in the other forms of the invention hereinbcfore described, the cars 32 afford a means of connection between the lever 23, with its movable core 21, and the ob ject to be pulled or shifted.

The longer arm 66 of the bell-crank lover aforesaid is connected as at 67 with the core of the minor magnet, whetherthe latter be of the species 15 Fig. VIII,or of the species 15 15 15 Fig. VII. In the case ofthe three phase system, the core consists of double hollow cylinders as 68, 68", of differentv metals according to approved practice. The

single core of themagnet 15 isindicated by p the numeral 68. 'The coils 15, 15, 15 are set in ashell orcasing 69, provided therefor at the lower end of the frame members 1 and 1; A cover 70 forms a closure for this shelL'in front. As represented in Figs.

VIIand VIII, a screw 30 carried by an extension 28 projecting rea-rwardly from the lower end of the lever 23 is arranged so as to be swung into contact with the underside of the same shell, and thereby operates to limit the outward swing of the lever 23, to which the core 21 is'attached.

In the wiring diagram, Fig. X, which corresponds to the arrangement of parts illustrated in Fig. VII, the numerals 75, 76 and 77 respectively designate line wires of a three phase system. As shown, the wire 77 is connected up with one terminal of the coil 15" the wire 76 is similarly connected with the coil 15; and the wire has a corresponding connection with the coil 15 ineluding a switch 7 8 therebetween. The other terminal wires for these three coils are respectively represented by the lines marked 7 9, 80 and 81 which are connected to a common header 82. The numerals 83 and 84 designate the terminal wires for the major magnet 15, which are arranged to connect with the previously mentioned wires 7 5 and 7 6 respectively, the wire 83 being coupled up by means of a switch 85. Whenever the connection between this switch and the wire 7 current is effected, over having it remain on the major magnet for the entire period during which the movable core remains therein. Notwithstanding that separate switches '78 and 85 have been shown for the operation of the major and minor magnets in this modified construction, it will be readily perceived that the automatic current switching arrangement diagrammed in Fig. VI can as well be used in conjunction with this modification. 7

An additional modification of the invention is shown in Figs. XI, XII and XIII.

In this modified form of the invention, the

frame is composed of similarly constructed" sides 1 and 1, united by upper and lower connecting pieces 2"" and 2 The sides are formed with arms 3, 4 and 5, and the irame is held as a whole to aprimary support by means of suitable bolts passing through bosses 9, on the opposite sides. Pivot pins 11* and 12 are supported in the arms 4 and 5, respectively. Above the arms 4 is mount-' ed a major electromagnet 15, abutting at its rear end'against the arm 3 and held in front by a clamp 17. A fixed core 20 projects forwardly from the arm 3, oppos te a movable core; 21, carried the upperJ-end'of an overbalancedlever 23,- pivoted at its lower endnon the pin 12. On .thepin :l'l ..is.ful-' crumedza bell crank: lever having arshort armIQ P extending towards the lever 23. A

, finger 25, projecting inwardly from the Mt ter is extended under the said short arm,

which is formed with a hook-shaped catch 26, adapted to engage. a correspondingly connectingpiece 2 of the frame, and limit the drop. of thesaid lever, when the core 21 V is liberated by the magnet and the catch 8 v is released by the latch. Ears 32 provided 90, transversely of "the frame.

externally on the lever 23, supply the same means of attachment "for the load to be" swith the other forms of construcmoved, tlon hereinbefore described;

The longer arm 66 of the aforementioned bell-crank lever'hasformed integral therewith, at its lower extremity a gear segment 87 with teethmeshing into a plmon 88, se

cured to a shaft 89,jou rnalled in bearings Upon the shaft89 'ismounted a rotor disc 91, between laminations 92, 93 carried by thebearings 90 .on both sides thereof, all of which pertain to an'induction motor,ofordinary construction.

94, 95 of a twophase system, with terminal. wires 96, v97 respectively leading therefrom, are placed intermediatelyof the laminationsf Oppositely connected windings Terminalwires 98, 99 Ilikewise lead from the electromagnet 15. When the electric current is afforded a continuous flow through the wires 98, 99, the

magnet -15 becomes energized and the core '21 actuated'thereby pulls the lever 23 in-" wardly against a load imposed 'upon the latter, art -'32, forinstance. In the meanwhile,

the electriccurrent is caused to ifiowaminterruptedly also: along the wires 96, 97 of the inductioninotor, tendingto rotate the pinion 88 in the direction indicated bythe arrow A in. Figs. XI and XII. The

pinion isheld in check, however, by the inactivity. of the bell-crank lever, when the hook portion ofthe catch 26 rides upon the j inner end of'the finger 25. But,-as soon as the finger, with its latch 27, arrives at. the

pointjwhere' it can be engaged by the catch,

the rotation of the pinion causes the shorter;

arm 2 of the bell-cranklever to be lowere d sufiiciently to permit engagement. While 7 the-current remains .on both-windings 94' and 95, the longer arm 66-.of the bell-crank:

mains energized.

lever ;is held in the position represented Fig. LXI whereby the load moving lever :23 is kept in quiescence, even though the currentbe turned'ofl the major magnet 159-.

'But, if the flow of current through either.

one of the terminal wires 96 and 97 is interrupted, the other terminal then becomes unable to .hold'the latch and catch engaged,

them apart. It is understood that when the currentiis taken off either wire, 96201. 97' it and the overbalancing of the lever 23 forces I has-been previouslydeviated from themagnet 15.

Although no separate wiring diagram has been furnished in connection with the struc-. ture exemplified in Figs. XI to XIII, it'is obvious that the .samecan be electrically connected up according to either of the" systems represented in Figs. VI andX.

, lVhile certain preferred embodiments of this invention have been shown and de scribed, it will be understoodthat changes inthe form, arrangements, sizes, proportionsan-d details thereof may be made without departing'fromthescope of the inventionas defined by the appended claims,

,Having described my invention what I desire to secure by Letters Patent and claim 1s V 1. A-device "of the class described comprising, in combination, a loa'd moving ele-' ment lncludinga core oscillatable there with, an electro=magnet acting thereupon,

and mechanical means positively maintaining the core stationary within said magnet as long asthe latter is energized. r

.2. A device of the class-described includcore adapted to be shifted thereby, an oscillatable element carrying said core, and mechanism 'c'oincident'ly' oscillating with said element assisting to retain the core in-"' ward during magnetization.

in combination, an electro-magnet, a'

3. Adevicefof the class described includ-" ing, in combination, an electro-magnet, a core drawnarcuatelythereinto, 'a load pulling element carried by said core towards said magnet, and mechanical means 'coact'mg with the latter to retain said element with l V the core in, its inward position while. it Are- 4. A device of the class described includ ing, in combination, a load actuating ale 7 ment, an electro-magnet :moving the same, P V

and automatically applied means assisting the energized 'magnet 1n maintaining said element in a predetermined location, said] self-releasmg when themagnet means being 1s deenerglzed. 1

ing, in combination, an electro-magnet, a

5. A; device of the'class described includ-' load moving element actuated thereby, and

conjoined 7 electrical and mechanical means 1 locking said element after actuation, the are rangement being such that the force of the 6. A device of the class described com prising, in combination, a load moving element including a core, an actuating electromagnet therefor, and retaining means operating to hold said elementv with the core in conjunction with the energized magnet, the

arrangement of the weight of the element and said core permitting self-release thereof from said means when the said ma net is deenergized.

7. A device of the class described including, in combination, a pair of eleetro-magnets of different power, a loadmoving element actuated thereby, a mechanical retainer engaging said element, and means for reducing the flow of electric current through said magnets, the reduced current serving to maintain the engagement of said retainer with the element.-

8. A device of. the class described including, in combination, amajor electro-magnet, a minor electro-magnct operable therewith either in shunt or in series, a load shitting element moved by said magnets while in shunt relation, a mechanical retainer engaging said element during the latter part of its advance, and means operating automatically to place the magnets in-series, thereby causing the element tube kept engaged.

' 9. A device of the class described conr prising, in combination, an electro-ma-gnet, a load actuating element including a core drawn by said magnet, and a retainer moved in the'same direction as said core c'oacting mechanically with the energized magnet in maintaining said element with the core .in a given position, said retainer automatically effecting the release of the latter prior totheretraction thereof upon demagnetization.

10. A deviceot the class described including, in combination, an electro-magnet, a

core actuated thereby, a support carrying said core tending to retract the same, and a retainer on said support counteractingthe retraction of andholding said support engaged while the energized core remains in an inward position, said retainer being movable together with the core and its support to ward and from the same end of sald magnet;

11. A device of the class described including, in combination, electro-magnets of different strength, a core common to both magnets arranged to be pulled'mainly by the stronger one thereof,- a support tending to retract said core, and a lock retaining said support chiefly through the agency of the weaker magnet.

12. A device of the class described includ ing, in combination, electro-magnets of dit ferent strength, a core actuated mainly by the stronger magnet, a support for said core tending to effect retraction thereof, a retainerengaging said support following the cores actuation, and electrical connections operating to hold said retainer in engagement by directing the electric current through the weaker magnet, the release of "he support from the retainer automatically taking place alter the electric circuit has been interrupted.

13. A device of the class described in cluding, in combination, major and minor electro-magnets placed in axial alignment one relatively to the other, opposed cores ar 'anged to enter said magnets from the outer ends thereof, a load actuating element moved principally by the core of the major magnet, a retainer engaging said element during the latter part of the movement of said core, and an electric connection automatically operating to direct the current first to the minor magnet upon the element becoming engaged by said retainer.

14. A device of the class described including, in combination, electro-magnets of different strength mounted at a distance one from the other, a core actuated by the stronger magnet, a load moving element carrying said core, a retainer engaging said element during the latter part of the advance thereof, and means primarily controlled by the minor magnet operable to maintain the element and said retainer in engagement, said means serving to direct the electric current firstto the weaker magnet after such engagement is effected.

15. A device of the class described including, in combination, an elcctro-magnet, a core actuated thereby, a supportior said core tending to effect retraction thereof, a retainer engaging said support after the core is drawn inward, and operative connections serving alternately to keep the electric current on said magnet during engagement of said retainer with the support, and to turn it} off for the release of the retainer.

16. A device of the class described ineluding in combination, electro-magne'ts of different power, a core moved mainly by the stronger magnet, a support elevated by said core, a retainer engaging said support when the latter is raised, an electric circuit encompassing both of said magnets and admitting of being primarily directed through the weaker magnet, and means operating to direct said circuit to the latter named magnet to maintain said retainer in engagement with the support, the breaking of the circuit releasing the holdof the retainer on the supis effected.

17. A'device of the class described includmg, in comblnatlon, an'electro-magnet, cores "entering the same from the opposite ends supports energized. V V V g 18. A device of the class described includ-i ing, in combinatiom an electro-magnet, a

thereof, supports respectively carrying said cores tending to efi ec't retraction thereof, and self-parting "means for retaining said together while the cores remain load movingelement actuated thereby, a retainer with a guide carried bysaid element, and a locking part held constantly. in superposed contact with saidguide was to auto matically-engage said retainer following. actuation of the element. i

A device of the class described includmg, in combination, an e'lectro-magnet, op

' posed cores actuated thereby, leversrespecing said cores,'a retainer connected up with tively carrying said cores, a locking part on one ofsaid levers, and a retamer on the other lever. arranged to engagesaid part when the cores are drawn together.

20. device of the class described includ-- ing, in combination, one or more electromagnets, a pair of opposed cores actuated thereby,; pivoted levers respectively carryone'of said levers, and a locking part capable ofexerting a binding action upon said: 'retainer said parthavlng a connection with the other lever whereby the locking part is brought into action when the cores are being moved inward.

21. A device of the class-described including, in combination, electro-magnets of difterent strength in circuit together, a load.

moving element actuated mainly by the stronger magnet, a retainer carried by said element, a locking part adapted to be 1611'- gaged by said retainer, and a shiftable mem-' ber acted upon by the retainer'whereby the electric current is deviated sothat sa d part can be maintained in position chiefly by the weaker magnet.

I A device of the class described including, in combination, electro-magnets of different power, an electriccircuit therefor, -opposed cores actuate-d primarily by the stronger magnet, levers respectively carrying said cores and tending to "effect retraction thereof, a pair of locking members adapted to retain one of said leversin its inward'position, said members being caused to engage each other when ithe'levers are oscillated inwardly with their respective cores drawn together, and a shifter in said.

circuit acted upon by one member so as to direct the current first through the weaker magnet and cause it to retain said member 7 in engagement withthe other member. 23. A'device of the class described including, in combination, electro-magn-ets of differentstrength in circuit together, a loadmoving 7 element actuated mainly by the stronger magnet, a pair of locking members adapted to retain said element in its inward Y position, a shifter acted upon by one of said I members whereby the electric current'is deviated to maintain the other member en'- gagedfchiefly through the weaker magnet until an interruption occurs in the circuit,

and resetting means for re-establishing the circuit also operated by the last named member'upon'release thereof by the first named.

member.

V 2a. A device of the'class; described including, in combination, electro-mag'nets' of edit i e'rent power, an electric circuit therefor, a'

load moving element actuated mainly by the stronger magnet,a retainer carried by said element, a locking partv arranged tomeet saidretainer and to be maintained in engagement therew th chiefly by the weaker mage. net, and means on the retainer adapting it to change said circuit by directing the electrio current first through each ,magnet in V alternation.

'25. A. device of the class described including, in combination, superposed magnets of different strength, a load moving element actuated by the stronger magnet, a retainer earned by said element, and a lever pivoted intermediately ofsaid magnets, said lever;

having one'arm designed to engage saidretainer and its other arm operatively en} gaged by the core of the weaker magnet.

26. A device of the character describedh comprising in comb nation, a pair of pivoted levers, one of which 18 adapted to moving a loadand the other has arms: o-tunequal lengths, opposed cores respectively carried by said levers, electricalmeans for drawing said cores with. the levers one towards the V opposed to the one moving the load, only so much of the current is required to .retain the load as will keep said elements together,

irrespective of the outward pull on the core of theilo-ad moving lever. r

27. A device :of the character described comprisingin combination, a pair of levers pivoted so as'to be overbalanced away from 7 each other, opposed cores respectively carr ed at the upper ends of said levers, elec trical means for drawing said cores with the levers substantially together, and retaining elements between the levers operating-to keep the same lockedlin their inward position while the current remains on the cores, and becoming disengagedupon the interruption thereof, 'wher'eafter the levers are released and permitted-to. swing out-.

wardly.

28. A device of the character described comprising in combination, a pair of overbalanced levers pivoted to oscillate oppositely one to the other, cores on said levers adapted to be brought together, electrical means actuating said cores, and retaining elements on the overbalanced levers arranged to become interlocked so as to hold the latter when the cores have been drawn inward, but parting automatically with the levers after the current is cut out.

29. A device of the character described comprising in combination, a pair of levers oscillatable (me toward the other, an electromagnet positioned intermediate of said levers, cores on the latter arranged to be drawn substantiall together by said magnet, and automatical y ope-rated retaining elements adapted tointerlock following inward oscillation of the levers.

30.,A device of the character described comprising in combination, a'load moving lever having its fulcrum substantially at one end, a core carried by said lever at the end remote from said fulcrum, an electromagnet adapted to actuate said core, and retaining means for the lever intermediate the ends thereof arranged ,to hold it in a predetermined position when said magnet is energized and to release the same upon the current being interrupted.

31. A device of the, character described comprising in combination, a pair of pivoted levers with opposed ends normally kept apart by gravity, cores respectively carried bysaid ends of the levers away from the pivots thereof, an electromagnet adapted to draw said cores substantially together, and self-parting retaining elements nearer the pivots of said levers arranged to interlock after the magnetized cores have approached each other and to be released with the levers as the cores are deenergized.

32. A device ofthe character described comprising in combination, a pair of levers arranged to oscillate on independent fulcrums oppositely one to the other, cores on opposed ends of said levers, electrical means functioned to draw said cores substantially together, and coacting retainers for the levers capable of locking the same intermediately of their said fulcrums.

33. A device of the character described comprising in combination, a pair of levers oscillatable toward and away from each other, opposed cores near the ends of said levers, electrical means adapted to draw said cores substantially together, and selfparting retainers for the levers brought into engagementby inward oscillation of the latter through-the action of said means, one of said retainers being located intermediate the ends of one'lever, and the other retainer tiltable thereagainst beyond the fulcrum of the second lever.

34. A device of the character described comprising in combination, a pair of levers oscillatable oppositely one to the other, cores on said levers, an electro-magnet adapted to draw in said cores, and coacting retaining elements projecting inwardly in tilting arrangement from said levers, said elements becoming interlocked when the cores have been broughtto their inner position by the energized magnet, and parting automatically with the levers as the cores are demagnetized.

35. A device of the character described comprising in combination, a lever ful crumednear one end, a core attached to the other end thereof, a load moving connection on said lever intermediate of its fulcrum and said core, an electromagnet actuating the latter, and a retainer for the lever acting thereupon in a direction to oppose the pull of the load. I

36. A device of the character described comprising -in combination, a load shifting lever pivoted substantially at one end, a core carried by the other end thereof, an electromagnet actuating said core, and retaining elements functioned to hold said lever when the core has been drawn inward by said magnet, one of said elements being connected to move with the lever and to be engaged by the other element in a plane at substantially right angles to the line of movement.

37. A device of the character described comprising in combination a pair of levers of different lengths pivoted one above the other, cores carried by opposed ends of said levers, anelectromagnet arranged to draw said cores substantially together, and retaining elements-for holding the levers interlocked when the cores have been brought to their inward position, said elements being located below the pivot of the shorter lever and to one side of the longer lever.

38. A device of the character described comprising in combination, a pair of oppositely oscillatable levers pivoted in superposed relation, cores carried by said levers,

an electromagnet adapted to draw said cores substantlally together, and interlocking re taining elements extending one through the I other in substantially right angular arrangement. A 39. A device of the character described comprising in combination, an'eliectromagnet, cores adapted to be drawn one towards the other by the magnet, levers of diverse lengths actuated by said cores and pivoted in variant relation thereto so as to have a differential oscillatory motion to and away from each other, and retaining elements coacting with said levers to interlock the same when pulled inward, the longer and slower moving lever being the first to reach its inner position while the shorter and quicker swinging lever moves out first when the deenergized magnet releases the cores. I

40. A deviceof the character described comprising in'combination, a pair of levers :osoillatable one towardsthe other, foppo sitely directed cores carried thereby, an'

ranged to draw in said levers,'retaining elements adapted to interlock upon inward movement of said levers, and means operating to limit the oscillatory motion of the latter soeas to control the positions of said elements.

42. A device of the character described comprising in combination, a pairof oppo sitel'y swinging levers,"cores' carried thereby,

an electromagnet adapted to actuate said} "cores, retaining elements capable of inter locking said levers 'afterthe cores have been actuated, and stops arranged tolimit the outward swing of the levers when released by said elements subsequently to the cores being deenergized.

43. Adev-ice of the character described comprising in combination, a lever, a core carr ed thereby, "an electromagnet capable of acti'iatin-g said core, a retainer coacting with the latter in holding said lever in a predetermined position, and a stop operating subsequently to demagnetization of the core, and releaseof said retainer to limitthe movementof the lever in a direction oppor site that to which it was brought by the action of said magnet oiithe core.

4A. A device of the character described comprising in. combination, an overbalanced lever pivoted near its lower end, a core car-.

.ried by the upper end thereofpan electro I'inagnet adapted to'd'raw said core, a re- 'tainer coacting with the core in maintain ing said lever in: its inward position, and a stop servingto checktheoutward swing of the lever following liberation of said retainer,through deenergizing of the core, a

' 4 5. Adeviceof the character described comprising in combination, a pair of oppositely oscillatable levers, cores respectivelyca'rried by the latter, electromagnet capableof drai'ving SfdlCl'V COI G-S substantially to gethenione of said levers'being adapted to a movefa load and provided with a catch, and

a'jstopoperating to arrest the load moving a leverji'n advanceof said other lever thereby I by said latch upon completion of the movemerit of the lastnamed lever placing the catch in position to be engaged 46. A device of the characteredescribed compi'isingin combinatioma load moving lever, a core carried thereby, an electromagnet adapted to actuate said core, a re-' tainer cooperating with the latter to hold said lever in a given position,stops'respect-ively located on opposite sidesof the ful VCIUID of the lever to check it in either direction relatively to thelpoint'of'retention, and means serving to change the contacting distance between said stops and thereby limit themovement of the lever.

47. dev ce ofthe charactervdescribed comprising in combination, a frame having spaced arms at different distances apart, an a electromagnet supported "therefrom, cores arranged to be drawn substantially together by the latter, and levers carrying said cores pivoted in the arms remote from said net. 97:1 48. A deviceof the character described comprising in combination, a' frame 'provided with sets of arms "spaced'from' one another, an electromagnetfat one end of; said frame, oppositely I oscillata'ble levers; 1

pivoted to said arms, oneat the end of the frame remote from said magnet a'ridthef other intermediately thereof, and cores on said levers positioned to be actuated by said: xmagnet.

, 49. A comprising: in combination, an} open frame, an electromagnet in the upper part of the same, a load moving lever plYott-bCltO'SWlIlg exter'iorly of said frame fromthe lower part thereof, another lever pivoted tooscillate' within-the frame oppositely, to said first named lever, 'cores'res'pectively' carried by j both levers in position tobe acted upon by! device of the character described o 'said magnet, and intermediateelements"cooperating to retain the levers while sa-idf cores are held magnetically together.

'50. A device of thechara'cter describedi comprising in combinat on, a frame'with;

ported: from theiippermostfset of arm s-of .110 armsextending forwardly therefrom at Cliff feren't elevations, an. electromagnet supsaid-frame,a load moving lever pivoted to the lowermost i arms so as to oscillate in front'of said .inagiiet, a coacting lever p1v} eted to the intermediate arms in positionvtoj swing in rear of the magnet concurrently l with saidload'inoviiig lever, cores' on both of said levers arrangedtobedrawn 111 by holdthe le -*er's inward while the coresfare" energized.

1120 the magnet from the opposite ends'thereof, and a pairof'retaining elements ioperati'ng in a: median plane between said arms to PQ j M SON; 1 

